package com.hmdp.utils;

import cn.hutool.core.lang.UUID;
import io.jsonwebtoken.lang.Collections;
import lombok.RequiredArgsConstructor;
import org.springframework.core.io.ClassPathResource;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.data.redis.core.script.DefaultRedisScript;

import java.time.Duration;
import java.util.stream.Collectors;
import java.util.stream.Stream;

public class SimpleRedisLock implements ILock{
    private final StringRedisTemplate stringRedisTemplate;
    private final String name;

    public SimpleRedisLock(StringRedisTemplate stringRedisTemplate, String name) {
        this.stringRedisTemplate = stringRedisTemplate;
        this.name = name;
    }

    private static final String KEY_PREFIX = "lock:";
    private static final String ID_PREFIX = UUID.randomUUID().toString(true) + "-";
    private static final DefaultRedisScript<Long> UNLOCK_SCRIPT;
    static {
        UNLOCK_SCRIPT = new DefaultRedisScript<>();
        UNLOCK_SCRIPT.setLocation(new ClassPathResource("unlock.lua"));
        UNLOCK_SCRIPT.setResultType(Long.class);
    }
    @Override
    public boolean tryLock(long timeoutSec) {
        String threadId = ID_PREFIX + Thread.currentThread().getId();
        Boolean success = stringRedisTemplate.opsForValue().setIfAbsent(KEY_PREFIX + name, threadId, Duration.ofSeconds(timeoutSec));
        return Boolean.TRUE.equals(success);
    }

    @Override
    public void unlock() {
        stringRedisTemplate.execute(UNLOCK_SCRIPT,
                Stream.of(KEY_PREFIX + name).collect(Collectors.toList()),
                ID_PREFIX + Thread.currentThread().getId()
        );
    }
}
